DESCRIPTION: (Adapted from the proposal's abstract) BIOTRACES Inc. has developed a novel Multiple Photon DetectionTM (MPDTM) system for isotopes which is a thousand times more sensitive than standard detection systems. The MPD enhanced immunoassay is a new technique appropriate for research and clinical facilities optimized for the highest sensitivity quantitation of biomolecules. The objective of the proposed research is to utilize this new technology to develop a fast, reliable and quantitative immunoassay for HIV-1 p24 antigen present in mother's milk. When compared with current "state of the art" ELISAs the MPD enhanced immunoassay permits about a 1,000 fold greater sensitivity. Quantitation on the level of about ten to fifty virions per ml of serum is expected. More specifically, this new assay for p24 antigen will be used in studies of the transmission of HIV-1 from mother to child. PROPOSED COMMERCIAL APPLICATION: NOT AVAILABLE